Field of the Invention
This invention relates to a water-depth measuring apparatus for a double bearing type fishing reel. More particularly, it is concerned with an apparatus which enables accurate determination of the length of a fishing line supplied from a spool supported rotatably in a reel body so that the line may be wound on the spool by a handle, and thereby enables the casting of the line to a predetermined depth again.
Description of the Prior Art
A double bearing type fishing reel in which the cast length of a fishing line is indicated is disclosed in published Japanese Utility Model Specification No. 99676/1980. According to this publication, the reel includes a computer provided in a reel body for storing data concerning the number of turns of a fishing line wound on a spool, the size of the line, and the rotation speed of the spool. The reel body is also provided with a setting device which transmits a set signal corresponding to the number of turns and size of the fishing line to the computer.
A detectable element is provided on either the spool or a rotor adapted for rotation with the spool, and a detector for the element is provided on the reel body. The detector detects the rotation speed of the element, and transmits a corresponding signal to the computer. This signal and the set signal cause the computer to produce a signal representing the cast length of the fishing line, so that it may be indicated by an indicator. The entire mechanism for determining the cast length of the fishing line is provided in the reel body, and the cast length is indicated by the indicator. Accordingly, a detector of this type may only be used with the reel into which it is incorporated.